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101.
102.
VG Za?nullin 《Canadian Metallurgical Quarterly》1996,36(4):561-566
The frequency of irradiation-induced recessive lethals has been studied in chromosomes 1 and 2 of Drosophila melanogaster. It supposed, that the higher level of mutability may be explained in destabilization of genotype. The essential part in induction of genotype destabilization replies the genome instability mechanisms. 相似文献
103.
G. E. Skvortsov 《Technical Physics Letters》1998,24(10):749-751
104.
NE Ordian AI Va?do VV Rakitskaia NV Shiriaeva FI Pro?mina NG Lopatina VG Shaliapina 《Canadian Metallurgical Quarterly》1998,125(4):443-445
Although behavioral and neuropsychological data regarding the existence of images for odors are inconclusive, reconsideration of earlier EEG work provides reasonably clear evidence for an inner nose. However, further EEG studies and neuroimaging data seem essential for conclusive demonstration of an inner nose. 相似文献
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N Murugesan Z Gu PD Stein S Bisaha S Spergel R Girotra VG Lee J Lloyd RN Misra J Schmidt A Mathur L Stratton YF Kelly E Bird T Waldron EC Liu R Zhang H Lee R Serafino B Abboa-Offei P Mathers M Giancarli AA Seymour ML Webb JT Hunt 《Canadian Metallurgical Quarterly》1998,41(26):5198-5218
Substitution at the ortho position of N-(3,4-dimethyl-5-isoxazolyl) benzenesulfonamide led to the identification of the biphenylsulfonamides as a novel series of endothelin-A (ETA) selective antagonists. Appropriate substitutions on the pendant phenyl ring led to improved binding as well as functional activity. A hydrophobic group such as isobutyl or isopropoxyl was found to be optimal at the 4'-position. Introduction of an amino group at the 2'-position also led to improved analogues. Combination of the optimal 4'-isobutyl substituent with the 2'-amino function afforded an analogue (20, BMS-187308) with improved ETA binding affinity and functional activity. Compound 20 also has good oral activity in inhibiting the pressor effect caused by an ET-1 infusion in rats. Doses of 10 and 30 micromol/kg iv 20 attenuated the pressor responses due to the administration of exogenous ET-1 to conscious monkeys, indicating that the compound inhibits the in vivo activity of endothelin-1 in nonhuman primates. 相似文献
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Diagnosis of pancreatic carcinoma: role of FDG PET 总被引:1,自引:0,他引:1
MT Keogan D Tyler L Clark MS Branch VG McDermott DM DeLong RE Coleman 《Canadian Metallurgical Quarterly》1998,171(6):1565-1570
OBJECTIVE: The purpose of this study was to investigate the role of positron emission tomography (PET) with 18F-fluorodeoxyglucose (FDG) in differentiating benign from malignant disease in patients with possible pancreatic malignancy. SUBJECTS AND METHODS: All patients with a possible diagnosis of pancreatic carcinoma based on CT or ERCP findings were eligible for inclusion in this prospective study. PET imaging of the abdomen was performed in 37 patients and was interpreted as positive if FDG activity in the pancreas exceeded background activity and as negative if activity was less than or equal to background activity. Semiquantitative analysis was performed by calculating a standardized uptake ratio. Studies were reviewed independently by two radiologists, and results were correlated with biopsy results and with CT and ERCP findings. Sensitivity and specificity of FDG PET for revealing pancreatic malignancy was determined. RESULTS: FDG activity in the pancreas was increased in 24 patients, and adenocarcinoma was diagnosed in 22 of these patients (92%). Two patients (8%) with increased activity had benign disease, including one patient with chronic pancreatitis who showed no evidence of tumor at laparotomy and one patient with a mucinous cystic tumor who showed no malignant features at laparotomy. FDG uptake was low or normal in 13 patients, 10 of whom (77%) had benign disease. FDG uptake was also low in three patients with adenocarcinoma, whose tumor size ranged from 2 to 4 cm in diameter. The mean standardized uptake ratio value for malignant disease was 5.1 (range, 1.0-10.1) and for benign disease was 1.9 (range, 0.0-5.8) (p < .001). The sensitivity of FDG PET for revealing malignant disease in the pancreas was 88% and the specificity was 83%. CONCLUSION: FDG PET is a sensitive and specific noninvasive technique for the diagnosis of pancreatic malignancy. 相似文献